FILING REFUND FOR EXPORT

As per circular 17/17/2017 :
No need to file refund for IGST paid on export , have show in table 6a of GSTR 1, & in 3b for that month .

The system designated by the Customs shall process the claim for refund and an amount
equal to the integrated tax paid in respect of such export shall be electronically
credited to the bank account of the applican

Aggred with pankaj sir answer

Dear Pankaj Sir, We are not doing export by paying tax, we do export with LUT.